Cryopreservation Effect on Proliferative and Chondrogenic Potential of Human Chondrocytes Isolated from Superficial and Deep Cartilage

[Abstract] Objectives: To compare the proliferative and chondrogenic potential of fresh and frozen chondrocytes isolated from superficial and deep articular cartilage biopsies. Materials and Methodology: The study included 12 samples of fresh and frozen healthy human knee articular cartilage. Cell proliferation was tested at 3, 6 and 9 days. Studies of mRNA quantification, protein expression and immunofluorescence for proliferation and chondrogenic markers were performed. Results: Stimulation of fresh and frozen chondrocytes from both superficial and deep cartilage with fetal bovine serum produced an increase in the proliferative capacity compared to the non-stimulated control group. In the stimulated fresh cells group, the proliferative capacity of cells from the deep biopsy was greater than that from cells from the superficial biopsy (0.046 vs 0.028, respectively, p<0.05). There was also a significant difference between the proliferative capacity of superficial zone fresh (0.028) and frozen (0.051) chondrocytes (p<0.05). CCND1 mRNA and protein expression levels, and immunopositivity for Ki67 revealed a higher proliferative capacity for fresh articular chondrocytes from deep cartilage. Regarding the chondrogenic potential, stimulated fresh cells showed higher SOX9 and Col II expression in chondrocytes from deep than from superficial zone (p<0.05, T student test). Conclusions: The highest rate of cell proliferation and chondrogenic potential of fresh chondrocytes was found in cells obtained from deep cartilage biopsies, whereas there were no statistically significant differences in proliferative and chondrogenic capacity between biopsy origins with frozen chondrocytes. These results indicate that both origin and cryopreservation affect the proliferative and chondrogenic potential of chondrocytes.Servizo Galego de Saúde; PS07/84Instituto de Salud Carlos III; CIBER BBN CB06-01-0040Ministerio Ciencia e Innovacion; PLE2009-0144Ministerio Ciencia e Innovación; PI 08/202

Sutura de menisco com implantes absorvíveis Meniscus suture with absorbable implants

Os autores avaliam clinicamente 19 pacientes (19 joelhos - 15 meniscos mediais e 5 laterais) submetidos à sutura de menisco, utilizando 2 tipos de implantes absorvíveis (ácido polilático) Arrow® e Clear fix®. O estudo compõe-se de 15 homens e 4 mulheres com idades entre 16 e 44 anos, com média de 26,8 anos. O tempo de seguimento médio foi de 24 meses, com mínimo de 18 e máximo de 32 meses. A técnica operatória constituiu-se da sutura de um ou ambos os meniscos (1 caso), via artroscópica com Arrow® em 15 pacientes e Clear fix® em 4. Dos 19 indivíduos, 6 foram submetidos à sutura meniscal isolada, 11 associada à reconstrução do LCA e 2 à reconstrução do LCA com osteotomia valgizante da tíbia. Os resultados foram avaliados segundo exame físico incluindo as manobras de Appley e Mc Murray. A avaliação funcional pré e pós-operatória do joelho foi realizada pela escala de Lysholm modificada. Todos os pacientes tiveram suas manobras meniscais negativadas no pós-operatório. A pontuação média pré-operatória segundo a escala de Lysholm foi de 39,8 subindo para 91,5 no pós-operatório. Os autores concluem que a sutura de menisco, utilizando implantes absorvíveis, tem se mostrado eficiente até o momento, e que tecnicamente ela é mais simples que a sutura convencional.<br>The authors clinically assessed 19 patients (19 knees - 15 medial meniscus and 5 lateral meniscus) submitted to meniscus suture using 2 kinds of absorbable implants (polylactic acid) Arrow® and Clear fix®. The study is composed of 15 males and 4 females, ages ranging 16 - 44 years old (average = 26.8 years old). The mean follow-up time was 24 months, ranging from 18 to 32 months, at most. The surgical technique was constituted of a suture in one or both meniscus (1 case), through arthroscopy with Arrow® in 15 patients and Clear fix® in 4. From the 19 individuals, 6 were submitted to isolated meniscal suture, 11 combined to ACL reconstruction and 2 to ACL reconstruction with tibial valgusing osteotomy. The results were assessed according to physical examinations including the maneuvers of Appley and Mc Murray. Pre- and postoperative functional evaluation of the knee was performed using a modified Lysholm scale. All patients had negative meniscal maneuvers postoperatively. The average preoperative score according to Lysholm scale was 39.8 reaching 91.5 postoperatively. The authors conclude that the meniscus suture using absorbable implants has shown to be efficient so far, and that, technically, it is simpler than conventional suture